1. Field of the Invention
The invention relates to a machine tool with a cooling apparatus that utilizes a thermoacoustic effect.
2. Description of Related Art
Rotation of a rotating shaft of a machine tool causes a bearing portion to generate heat. In some machine tools, a cooling apparatus is used to cool the bearing portion in order to prevent seizure of the rotating shaft resulting from thermal expansion of the bearing portion caused by the heat generation. See, for example, Japanese Patent Application Publication No. 2003-117770 (JP 2003-117770 A).
A cooling technique utilizing a thermoacoustic effect is disclosed in Japanese Patent Application Publication No. 2000-205677 (JP 2000-205677 A).
The technique described in JP 2003-117770 A includes the cooling apparatus to cool cooling oil that cools the bearing portion. Energy is needed to operate the cooling apparatus.
JP 2000-205677 A describes a technique applied to cooling that utilizes a thermoacoustic effect for housing, warehouses, agricultural greenhouses, and in-vehicle coolers, but discloses no applied method useful for machine tools.